高等学校化学学报 ›› 2017, Vol. 38 ›› Issue (12): 2296-2305.doi: 10.7503/cjcu20170181

• 物理化学 • 上一篇    下一篇

草酸盐热分解法制备CeO2负载CuO催化剂用于CO优先氧化反应

王成1, 郭丽红1,2, 李新刚1(), 马奎1, 丁彤1(), 王新雷1, 程庆鹏1, 田野1   

  1. 1. 天津化学化工协同创新中心, 天津市应用催化科学与工程重点实验室,天津大学化工学院, 天津 300354
    2. 河南工业大学化学化工学院, 郑州 450001
  • 收稿日期:2017-03-27 出版日期:2017-12-10 发布日期:2017-11-13
  • 作者简介:联系人简介: 李新刚, 男, 博士, 教授, 主要从事多相催化方面的研究. E-mail: xingang_li@tju.edu.cn.丁彤, 女, 博士, 副教授, 主要从事环境催化方面的研究. E-mail: d_tong@tju.edu.cn
  • 基金资助:
    国家自然科学基金(批准号: 21476159, 21476160)和天津市自然科学基金(批准号: 15JCYBJC23000)资助

CuO Catalyst Supported on CeO2 Prepared by Oxalate Thermal Decomposition Method for Preferential Oxidation of CO

WANG Cheng1, GUO Lihong1,2, LI Xingang1,*(), MA Kui1, DING Tong1,*(), WANG Xinlei1, CHENG Qingpeng1, TIAN Ye1   

  1. 1. Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin Key Laboratory of Applied Catalysis Science and Engineering,School of Chemical Engineering & Technology, Tianjin University, Tianjin 300354, China
    2. School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China
  • Received:2017-03-27 Online:2017-12-10 Published:2017-11-13
  • Contact: LI Xingang,DING Tong E-mail:xingang_li@tju.edu.cn;d_tong@tju.edu.cn
  • Supported by:
    † Supported by the National Natural Science Foundation of China(Nos.21476159, 21476160) and the Natural Science Foundation of Tianjin, China(No.15JCYBJC23000)

摘要:

采用草酸盐热分解-浸渍法制备了一系列不同CuO负载量的CuO/CeO2催化剂, 并将其用于CO优先氧化(PROX)研究. 当CuO负载量为10%时催化剂活性最高, 具有温区最宽且温度最低的CO完全转化窗口(96~160 ℃), 并且当反应温度低于131 ℃时, 产物中CO2选择性始终保持100%. 研究结果表明, 当负载少量CuO时, Cu2+离子会进入CeO2晶格形成固溶体; 进一步提高CuO负载量会导致CuO在CeO2表面聚集. 对于CuO/CeO2催化剂, 形成Cu-Ce固溶体会在催化剂表面生成大量的表面氧空位和Ce3+; Ce3+则与Cu2+作用产生更多的表面Cu+, 而Cu+是CO PROX的活性中心, 因此表面Ce3+含量的提高和Cu-Ce之间相互作用的增强是活性提高的主要原因. 与普通沉淀-浸渍法制备的CuO/CeO2催化剂相比, 草酸盐热分解-浸渍法制备的催化剂更有利于Cu-Ce固溶体的形成, 从而具有更多的表面Ce3+和更强的表面Cu-Ce相互作用, 因此具有更高的CO优先氧化活性.

关键词: 草酸盐热分解法, CuO/CeO2催化剂, CO 优先氧化, 强相互作用, 表面Ce3+

Abstract:

A series of CuO/CeO2 catalysts with different CuO loadings was prepared via oxalate thermal decomposition-impregnation method for the CO preferential oxidation(PROX) reaction. The catalyst with 10% CuO loading has the best activity, with the lowest and the widest CO full conversion temperature window of 96—160 ℃, and 100% selectivity to CO2 below 131℃. The results indicate that the Cu-Ce solid solution is formed when a small amount of CuO is loaded. However, the increased CuO loading will result in the aggregation of CuO on the surface of CeO2, which is unfavorable to form the solid solution. For the CuO/CeO2 catalysts, the formation of Cu-Ce solid solution can inevitably generate surface oxygen vacancy and Ce3+, which can react with the Cu2+ to produce Cu+ through the balance of Ce3++Cu2+ \(\rightleftharpoons\) ? Ce4++Cu+. As the Cu+ is the active center for the CO PROX, the increased surface Ce3+ content and the strengthened interaction between CuO and CeO2 can enhance the CO PROX activity of the catalyst. Compared with the CuO/CeO2 catalysts prepared by precipitation-impregnation method, the catalysts prepared by oxalate thermal decomposition-impregnation method have the higher surface Ce3+ content and stronger interaction between Cu and Ce, resulting in the better CO PROX activity.

Key words: Oxalate thermal decomposition method, CuO/CeO2 catalyst, CO preferential oxidation, Strong interaction, Surface Ce3+

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